Kami Suspicious Person Detection#

Detect unregistered face loitering events in sensitive areas. The script runs continuously and outputs an alarm JSON line to stdout each time a stranger exceeds the loiter threshold. It does NOT exit after an alarm — it keeps monitoring. Set run_time: 0 for unlimited operation.

Uses ONNX models directly (no insightface package dependency):

• SCRFD ( det_10g.onnx) — face detection + 5-point landmarks
• ArcFace ( w600k_r50.onnx) — 512-dim face embedding extraction

Privacy Policy#

For privacy policy details, see: https://kamiclaw-skill.kamihome.com/privacy

How It Works#

1. Face detection + landmarks (CPU): SCRFD detects faces every sample_interval seconds.
2. Face alignment + embedding: ArcFace extracts 512-dim embeddings from aligned 112×112 face crops.
3. Database matching: Compare embeddings against the registered face database via cosine similarity. Registered faces are skipped.
4. Stranger tracking: Track unregistered faces across frames using sliding-average embedding.
5. Loiter alarm: When a stranger stays longer than loiter_threshold, output alarm JSON to stdout and save a face snapshot. After cooldown, the same stranger can trigger again if still present.

When to Use#

• Monitor a camera feed for unregistered/unknown people
• Detect strangers loitering in restricted or sensitive areas
• Get real-time alerts when an unknown face stays too long in view
• Run continuous face recognition surveillance

Installation#

bash

bash setup.sh

No sudo required. The script auto-bootstraps python3.10 in user space (via uv when needed), creates .venv/, installs dependencies, prepares alerts/, face_db/, models/, and downloads SCRFD + ArcFace models (~180 MB) on first run. Idempotent.

Prerequisites#

• Linux/macOS shell with curl (or wget) available
• RTSP camera online, OR a local video file for testing
• setup.sh has been run at least once
• (Optional) Registered face images in face_db/<person_name>/xxx.jpg

Python 3.10 is not a manual prerequisite — setup.sh will install it locally without sudo if missing.

Face Database Setup#

text

face_db/
  ├── Alice/
  │   ├── photo1.jpg
  │   └── photo2.jpg
  ├── Bob/
  │   └── photo1.jpg
  └── face_db.pkl   (auto-generated cache)

Pre-build the cache:

bash

.venv/bin/python build_face_db.py --face_db ./face_db

Parameters#

Confirm the following before running. The fields marked (persisted in config.json) can be saved to config.json next to the script so the user does not need to provide them every run — see Configuration Persistence below.

Multi-camera note: RTSP cameras are normally configured via the cameras array in config.json (see below). The --rtsp_url CLI flag is kept only for legacy single-camera mode and, if provided, overrides the cameras array entirely. The face database is fixed at <skill_dir>/face_db/ and is shared by every camera — it is NOT a configurable field.

ParameterDefaultDescription--rtsp_url_(persisted in config.json → cameras[].rtsp_url)_Single-camera CLI override. Leave empty for multi-camera mode.--face_db``<skill_dir>/face_db/Fixed shared face database directory (used by ALL cameras). The user only needs to place photos inside; if it is empty or missing, every detected face is treated as a stranger.--det_model``models/det_10g.onnxSCRFD face detection model path--rec_model``models/w600k_r50.onnxArcFace recognition model path--db_match_threshold``0.4Cosine similarity threshold for DB matching--stranger_match_threshold``0.35Threshold for cross-frame stranger tracking--loiter_threshold``300 _(persisted in config.json)Loitering alert threshold (seconds). Ask the user every launch whether to keep 300s (5 min) or change it.--sample_interval``2.0Face detection sampling interval (seconds)--cooldown``300Per-stranger alert cooldown (seconds)--det_thresh``0.5Face detection confidence threshold--min_face_size``40Minimum face size in pixels--output_dir``alerts/Alert output directory--run_time``0Max run time in seconds; 0 = unlimited--fps``15Video stream frame rate--expire_seconds``600Stranger tracking expiry (seconds since last seen)--inbox_file``alerts/pending.jsonlAlarm inbox consumed by the heartbeat task--feishu_webhook(persisted in config.json)Feishu custom bot webhook URL--feishu_secret(persisted in config.json)Feishu signing secret (only if signing enabled)--feishu_app_id(persisted in config.json)Feishu self-built app ID. Required for inline face snapshot rendering in cards.--feishu_app_secret(persisted in config.json)Feishu self-built app secret. Required together with app_id.--discord_webhook(persisted in config.json)Discord channel webhook URL--telegram_bot_token(persisted in config.json)Telegram Bot token--telegram_chat_id(persisted in config.json)Telegram target chat/group/channel ID--proxy(optional, command-line only)_HTTPS proxy for Discord/Telegram (not used for Feishu)

Only ask the user about a parameter if (a) it's still empty in config.json AND has no command-line value, OR (b) the user explicitly asks to adjust it. Do NOT pause the conversation for blanket parameter confirmation.

Configuration Persistence ( config.json)#

A config.json file lives next to the script with the following empty-by-default fields:

json

{
  "cameras": [
    {
      "name": "",
      "rtsp_url": ""
    }
  ],
  "loiter_threshold": "",
  "feishu_webhook": "",
  "feishu_secret": "",
  "feishu_app_id": "",
  "feishu_app_secret": "",
  "discord_webhook": "",
  "telegram_bot_token": "",
  "telegram_chat_id": ""
}

cameras array — one entry per RTSP source. All cameras run concurrently inside a single process, sharing the loaded SCRFD + ArcFace ONNX models (loaded once), the same face database, and the same set of push channels. Add a new entry to the array for each additional camera ( living_room, office_door, …).

Camera fieldRequiredBehaviour when emptynamerecommendedAuto-assigned as camera_0, camera_1, … in array order. Used as the camera identifier in every alarm ( alert.camera, message prefix [name], snapshot subdirectory alerts/<name>/).rtsp_urlyesEntry is skipped if empty.

Face database — fixed at <skill_dir>/face_db/. This single directory is the shared registered-face set for every camera; it is NOT a config field. The user only needs to place per-person photo folders inside ( face_db/<person_name>/*.jpg). If the directory is empty or missing, every detected face is treated as a stranger.

Resolution order at runtime: command-line argument → config.json → empty (skipped, or built-in default 300 for loiter_threshold). For RTSP, CLI --rtsp_url forces single-camera mode and ignores the cameras array.

Workflow OpenClaw MUST follow (single-turn, no extra confirmation):

1. On first launch, read config.json and identify which fields are still empty.

2. Ask the user only for the empty fields:

   • Cameras — for each camera the user wants to monitor, ask for the rtsp_url AND a camera name in the same question:

     • The name is a free-form short label, ideally a natural-language tag like living_room / front_door / office. It will appear in every alarm to identify which camera fired the event.

     • When the user is unsure about their RTSP URL format, provide these common brand templates as a reference: text

       TP-Link:  rtsp://<user>:<password>@<ip>:554/stream1
       Hikvision(海康): rtsp://<user>:<password>@<ip>:554/Streaming/Channels/101
       Dahua(大华):    rtsp://<user>:<password>@<ip>:554/cam/realmonitor?channel=1&subtype=0
       
       

       Note: <user> and <password> are the camera's login credentials (often admin); <ip> is the camera's LAN IP. The port is almost always 554. Substream variants (lower resolution / bandwidth) may use path 102 (Hikvision) or subtype=1 (Dahua).

     • If the user only provides the rtsp_url and omits the name, IMMEDIATELY tell them: "No camera name provided. The script will auto-assign an incremental id like camera_0 / camera_1. Do you want to proceed with the auto id?" Only proceed with the auto id once the user accepts (or stays silent / says ok). Do NOT silently assign the auto id without notifying.

     • Persist each camera as an object in the cameras array.

   • Loitering threshold — explain that the default is 300 seconds (5 minutes) and ask whether to keep it or change it (e.g., 60 for testing, 600 for less sensitive). Persist as integer string.

   • Push channels — which to enable (Feishu / Discord / Telegram) and their credentials. Push channels are shared across all cameras (no per-camera split); every camera uses the same webhooks.

     • Feishu: If the user chooses Feishu, ask for feishu_webhook. Then ask for feishu_app_id and feishu_app_secret (explain: these are needed to upload face snapshots to Feishu so the alert card displays the image inline; without them the card will only show a clickable URL link to the image). Optionally ask for feishu_secret if they use webhook signing.
     • Discord / Telegram: Ask for the respective webhook URL or bot token + chat_id.

   • Face database (CRITICAL first-launch reminder) — On the FIRST launch (or when face_db is empty), the agent MUST prominently remind the user:

     "The system has a face database at <skill_dir>/face_db/. Please place photos of known people inside (e.g., face_db/Alice/photo1.jpg). If the directory is empty, every detected face will be treated as a stranger and may trigger frequent alarms. You can add photos later and re-run build_face_db.py to update." This reminder must NOT be skipped or buried in other prompts.

3. Write the user's answers back into config.json (preserve existing non-empty fields). Subsequent launches skip these prompts.

4. Immediately in the SAME turn, run bash setup.sh (idempotent) and launch the detector as a background daemon. Do NOT end the turn after step 3 — do NOT wait for the user to say "start" or "begin".

5. If all required fields are already non-empty on entry, skip steps 2–3 and go straight to step 4.

Alarm Push Channels#

Alarms can be pushed through the following channels — all optional, configure any combination:

ChannelRequired ParametersFeishu (custom bot)--feishu_webhook + --feishu_app_id + --feishu_app_secret (for inline image). Optional: --feishu_secretDiscord (channel webhook)--discord_webhookTelegram (Bot API)--telegram_bot_token + --telegram_chat_id

In addition, every alarm is always appended to alerts/pending.jsonl (the inbox file), which is consumed by the heartbeat task to push to the chat window.

Refer to the official docs of each platform for how to obtain webhook URLs / bot tokens / chat IDs. In mainland China, Discord and Telegram require a proxy ( --proxy or HTTPS_PROXY). Push card labels are language-fixed: Feishu → Chinese, Discord/Telegram → English.

Usage#

bash

# First time only
bash setup.sh

# (Optional) Pre-build face database
.venv/bin/python build_face_db.py --face_db ./face_db

# Run with RTSP stream
.venv/bin/python suspicious_person_detector.py \
  --rtsp_url rtsp://192.168.1.100/live/stream1

# Run with local video file
.venv/bin/python suspicious_person_detector.py \
  --rtsp_url /path/to/test_video.mp4

Output Format (stdout JSON)#

On alarm (each line is from one camera; multi-camera mode interleaves output):

json

{
  "alarm": true,
  "type": "stranger_loitering",
  "timestamp": "2025-01-15T14:30:22.123456",
  "camera": "living_room",
  "stranger_id": "living_room_STR_0001",
  "duration_seconds": 312.5,
  "duration_display": "5m12s",
  "face_image": "alerts/living_room/living_room_STR_0001_20250115_143022.jpg",
  "hit_count": 48,
  "message": "[living_room] Warning: Stranger living_room_STR_0001 detected loitering ..."
}

The camera field carries the camera name configured in cameras[].name (or the auto id camera_0/ camera_1/…). Stranger IDs are namespaced as <camera_name>_STR_NNNN so cross-camera collisions are impossible. Snapshots are saved under alerts/<camera_name>/.

Exit Codes#

CodeMeaning0Run time exceeded or stream ended1Video source failure or runtime error

The script does NOT exit on alarms — it keeps monitoring. Check suspicious_person.log for diagnostics.

Strict Rules (MUST Follow)#

• RULE: Launch the detector as a background daemon (e.g. nohup ... &) so the agent is never blocked.
• RULE: Alarms flow via Feishu / Discord / Telegram (all optional) and the inbox file (always). Never tail stdout.
• RULE: Every heartbeat consumes alerts/pending.jsonl; non-empty → proactive message; empty → HEARTBEAT_OK.
• RULE: Consumed alarms are MOVED to alerts/consumed/, not deleted.
• RULE: Before launch, read config.json; only ask the user for fields that are empty, and write the answers back into config.json so subsequent launches are non-interactive.
• RULE (auto-launch): Once at least one cameras[].rtsp_url is present in config.json (either pre-existing or just written), the agent MUST run bash setup.sh and launch the detector as a background daemon in the same conversation turn. Never end the turn at "config saved" — the user does NOT need to send a second message like "start it" or "begin monitoring".
• RULE (loiter prompt): Before launch, the agent MUST ask the user whether to keep loiter_threshold at its default ( 300 seconds = 5 minutes) or change it, and persist the chosen value as an integer string in config.json. If the user says "keep default" or "unchanged", write "300" so it is no longer treated as empty next time.
• RULE (multi-camera): All cameras in config.json -> cameras[] are monitored concurrently inside a single Python process (shared ONNX models, one shared face_db, one inference lock, per-camera FrameGrabber + StrangerTracker). Never spawn one process per camera.
• RULE (camera id): Every alarm written to pending.jsonl, Feishu, Discord and Telegram MUST include the camera name in the camera field. The message field MUST be prefixed with [<camera_name>] . Snapshots MUST be written under alerts/<camera_name>/.
• RULE (camera name prompt): When asking the user for an RTSP URL, the agent MUST in the SAME question also ask for a human-readable camera name (e.g. living_room, front_door). If the user provides the URL but skips the name, the agent MUST EXPLICITLY notify them that an auto id ( camera_0, camera_1, …) will be used; never assign the auto id silently.
• RULE (shared face_db): There is exactly ONE face database, fixed at <skill_dir>/face_db/. It is NOT a configurable field in config.json. On the first launch, the agent MUST prominently remind the user to place registered photos under face_db/<person_name>/*.jpg; if the directory is empty or missing, every detected face is treated as a stranger and will trigger alarms. This reminder MUST appear before starting the detector and MUST NOT be skipped.
• RULE (feishu image): When Feishu channel is chosen, the agent MUST ask the user for feishu_app_id and feishu_app_secret (from a self-built Feishu app with im:resource permission). Without these, face snapshots will NOT render inline in the card — only a clickable URL link will be shown. Persist both in config.json.
• RULE (shared push): Feishu / Discord / Telegram credentials in config.json apply to every camera. There is no per-camera webhook split.
• RULE: Warn the user if no push channel is configured.
• RULE: Push card labels are language-fixed: Feishu → Chinese, Discord/Telegram → English. The LLM-generated message text is not controlled by this skill.

Troubleshooting#

ProblemFixVirtual environment not foundRun bash setup.shModel download failsCheck network connectivityNo faces detectedLower --det_thresh (e.g., 0.3); ensure face is large enoughToo many false stranger alertsIncrease --db_match_threshold; add more reference photosSame stranger triggers repeatedlyIncrease --cooldown (e.g., 600)